When Baby Boomers were teenagers and young adults, marijuana use was broadly accepted among youth cultures, but by the late 1980s marijuana and other so-called soft drug use was socially disparaged. Today the pendulum is swinging back and marijuana use has become much more widely tolerated to the point where municipal, county, and state laws decriminalizing marijuana possession have been enacted across the country. In order to investigate the health and social consequences of changing political and social contexts, we plan to conduct in-depth life history interviews with marijuana users divided into two cohorts defined by varying social roles and cohort experiences : 60 early Baby Boomers (born between 1946-1957) and 60 late Boomers (1958- 1964) who are regular users. We hope to discover the differences and similarities between how early and late Baby Boomers perceive their own and others' marijuana use, their attitudes, their actual use patterns, and their perceptions of its health and social consequences. The overarching aim of this proposed 36-month qualitative project is to conduct in-depth interviews with 120 (60 women and 60 men) primary marijuana users in order to address the question: What are the differences and similarities between early and late Baby Boomers' beliefs, practices, and health and social consequences of marijuana use and how do they change over marijuana use careers? To be included in the sample, participants must self-identify as current marijuana users, be born between 1946 and 1964 and they must have used marijuana a minimum of 24 times in a six-month period or at least once a week. At no point in their drug using careers will they have been in treatment for heroin, powder or crack cocaine, methamphetamine, other club drugs, psychedelics, or prescription drugs. We will include those who have been in treatment for their marijuana use. We will exclude potential participants who self-report problems with or treatment for alcohol in the year prior to interview. These inclusion and exclusion criteria are designed to focus our study on older primary marijuana users to examine their marijuana use specifically and to discover their unique use trajectories. Understanding the experiences of older marijuana users will shed light on future use patterns and potential health and social consequences for those young adults who continue to use marijuana into older adulthood. In depth understanding of older marijuana users, beliefs and practices will allow us to modify existing prevention and intervention efforts currently targeting younger populations to focus on the growing population of older adults. Public health initiatives need to be tailored not just to cultural dimensions (e.g. rce and ethnicity) but also to age and aging. People have different motives for marijuana use, which can vary over time, and this requires different approaches to designing intervention strategies. By identifying the social and health related issues of early and late Boomers we can strengthen the public health initiatives not only for Baby Boomers but for younger generations, because we will demonstrate the role marijuana plays during the natural physical and mental aging process.